


Assorted Smutty Nonsense

by tluthal



Category: Undertale (Video Game)
Genre: Multi
Language: English
Status: In-Progress
Published: 2018-12-07
Updated: 2019-01-10
Packaged: 2019-09-13 07:34:06
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 2,760
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16888308
Author URL: https://archiveofourown.org/users/tluthal/pseuds/tluthal
Summary: Assorted undertale au smut, written primarily about my ocs and their pairings. Specific tags at the beginning of each chapter.





	1. Ouch

**Summary for the Chapter:**

> Prompt: Sexual Discovery, Piercings, Accidental Stimulation
> 
> Pairing: Solo, featuring Rue of Lustfell

Rue gently bit fingers clad in soft leather. Even before they’d fallen, they’d been aware of their love of gloves, but since falling, they’d had to amass quite a collection of them. The monsters of this timeline couldn’t stand physical contact with them for the most part, seeing their unshielded soul as a challenge. They had quickly taken to wearing gloves after they’d realized what the issue was, and frankly it’d be disgusting not to change and wash them regularly. Lost in thought, their fingers pushed further into their mouth absently, uncurling until they caught against one of the elegant gold piercings in their tongue. When they’d fallen, they’d only had one. They’d gained another on a dare, and now they couldn’t quite stop fiddling with them. A single monster candy had healed it instantly, which had served only to encourage them to explore their options down here even more.

The amused piercer had asked if they were a masochist after a few. They’d denied it of course; perish the thought, but it had set them to wondering. The open sexuality of the underground had exposed them to things they’d always denied about themself, forcing them to re-examine their own assumptions about both themself and others. Was it really so far-fetched that they might enjoy experiencing pain when it wasn’t just the everyday aches and pains they’d learned were as much from the state of their soul as the dreadful state of their body?

A sudden noise startled them out of their thoughts and their eyes darted to their door, head jerking a little. They’d been twirling the piercing between their fingers though and it yanked, hard enough to startle a cry that was muffled around their own fingers. They bit down on the offending appendages hard, one eye screwing shut against the immediate watering of their eyes in response. Their breath caught in their throat and they froze, shivering. They were caught between a spike of arousal and a spike of fear. Shivering turned to shuddering as they realized abruptly that they were both safe, and all the more aroused for having been spooked. Their nipples hardened and they squirmed a little in their chair. They had a few days off from working at Grillby’s due to one of the irritations of humanity and if a little jolt of pain and fear was going to make them react like this... Rue forced their jaw to relax, drawing their fingers out of their mouth with a lewd sound.

They had rope and all the recovery time in the world here, and even if they were caught out... would anyone even care? Cad and _his_ tendencies were more than tolerated, after all. They grinned to themself and made a mental note to take a few pictures. Rue wiggled in their seat more at the thought, both shameful and tantalizing, and finally gave up all pretense of contemplation. They slammed their journal closed and dropped their thoroughly chewed pen onto it and began to strip.

Alone in their room, their coat had already been hanging by the door, so they started with the boots, loosening the hidden clasps that kept them up and sliding muscular legs out of them. They set them to the side, carefully unbuckling their belt and coiling it neatly to rest on the desk next to their journal. Their shorts were next as they thumbed them open carefully. The soft leather and softer fur shorts were their favorite piece of clothing after their coat, after all, and it simply wouldn’t do to damage them - even though it took quite a bit of hip-shimmying to get them past their butt now. Perhaps their body was recovering faster than they thought it was... A bit more wriggling finally freed their from the shorts and they set them carefully on their chair. Their sun pendant was lifted off and deposited by the journal, then they carefully peeled their sleeveless, high-necked top off. That was folded and placed on top of the shorts. They could see glimpses of pearlescent blue scales, tinted red at the tips, on their shoulders and chest now. their hands ran lightly over their soft green lace and gold ribbon bra, the leather encasing their fingers drawing a luxurious shiver from their.

They debated leaving them on for a moment before deciding against it; anyone who touched them after would be able to tell immediately. They delicately caught the fingertips of one glove with their teeth, pulling the glove loose with practiced ease, before repeating the procedure and laying the gloves out on their desk. They took half a step to the side and looked at the mirror hanging on the back of the door. Though their outer layers were considered conservative by the monsters, their choice of underwear had met with quite a bit of approval. Black semi-sheer stockings covered their legs, held up by a gorgeous dark red garter belt that matched their shorts. Delicate golden ribbons and green lace made up their bra and panties, multiple ribbons criss-crossing their ample chest and ass. they hadn’t noticed their hips and rear filling out mainly due to the adjustable nature of their underthings; the panties tied on and the bra needed careful adjusting in the first place. The soft lace did nothing to hide pretty nipple piercings; small gold rings caught the light of the room.

Almost hesitantly they raised their hands to their chest, palms rubbing over the soft mounds so their sharp nails wouldn’t catch on the lace and ruin their underthings. They twisted their hands a little, catching their nipples and pinching and tugging at them, first gentle, then hard enough to make their breath catch. Their teeth sank into their lip, holding back a soft, eager sound. Their thighs pressed together and they shuddered, pinching harder and closing their eyes, holding it longer than they’d thought they could stand. A ragged gasp escaped them as they finally released their hold. They reached back, quickly undoing the clasps to their bra and tossing it aside, untying their panties almost as fast.


	2. Be Good

**Summary for the Chapter:**

> Prompt: Petplay, breathplay
> 
> Pairing: Marrow [Fell Sans] / Conquerer (p **ASSi** fist fell timeline)
> 
> Howl belongs to GetMcDunkedOn.

**“be a good girl.”** The guttural voice growled in her ear. The skeleton currently pinning her arms behind her with one massive hand was large enough to manhandle her in any way he wanted, but one slap - back when they first met - had been all it had taken to convince him to never touch her without her permission.

Dove had freed monsterkind a month ago, after forcing every last monster to kneel at her feet or be knelt. She had needed, and gotten, help to do it… And now she needed help again. Howl had given her the tools to conquer the underground, but he had also given her a desperately needed stability and person to _trust_ to counter the vicious voice in her head when it became overwhelming. It had–

Her thoughts cut off with a wet choke as Marrow pulled a broad, leather collar tight around her throat. She’d missed him securing her arms with a pair of leather cuffs digging into her wrists and forearms, just tight enough to force her back to arch and her chest to stick out. The broad skeleton held it tight until her eyes were rolling to meet him, her face starting to darken from red to purple, then eased it a few loops loser to let her breathe past it - with difficulty, of course.

“GHH!”

 **“heh. mind on me, kitten. i’m the only thing you should be thinking about right now. keep those pretty eyes on me.”** His thumb forced its way into her mouth, pressing down on her tongue. It didn’t take any prompting for her to suck on it, tongue dragging over the phalanges lewdly. **“that’s it, good girl.”** His other hand pushed her shirt - originally his - up to fondle her breasts, until her eyes were mostly closed, fighting not to roll back into her head. When he was certain she was focused on the sensations, he pulled his hands away to clip a leash to her collar.

Dove shuddered, watching Marrow through eyes that didn’t quite want to focus. A moment later that didn’t matter as he gently removed and sat aside her glasses, settling back against his bed and pulling her into his lap. She couldn’t catch herself with her arms bound, and found herself sprawled across his femurs with her legs spread wide. Before she could try to even lift her head out of a knot of dirty sheets, blue magic was holding her in place.

 **“thatagirl. this really gets you off, huh?”** Two fingers slid into her as deep as they could go, followed by a third when he didn’t feel enough resistance. **“that’s what I thought. pretty little stray like you hasn’t always been a stray. you know what to give your master.”** Her hips moved without any conscious input, rocking into his thrusts as the magic holding her still eased. He still wouldn’t let her raise her head or shift her legs below the knee, but this pleased him as it was. Vile thoughts tried to rise once more, disparaging her choice of partner, the vulnerability of the situation, and her willingness to chase pleasure, but when she started to still Marrow simply thrust into her harder again, making her gasp in a desperate breath and bite into the sheets. Her walls clenched around him and she whined, the sound much louder than she’d intended.

**“what’re you whinin’ about, huh? you want more, pretty kitty?”**

“HHHN–” She lifted her hips a bit more, demandingly.

 **“heheh. waterfall butt. alright, alright.”** He lifted her with a gentle touch, settling her with her back against his chest, kneeling across his lap, and pulled his shorts down just enough to free his cock.

“DUDE, GROSS.”

 **“kitties don’t talk.”** He growled, pulling the collar tighter again until her legs were shaking and her eyes had rolled back, making sure she was one good touch away from cumming. His cock caught against her entrance easily and his free hand settled against her hip before slamming her down. She let out a tiny, whimpery moan as she twitched and fluttered around his cock. She could barely take him, and as sensitive as her body was to magic, a tight collar and thick cock were more than enough to toss her over the edge.

Dove sagged bonelessly against Marrow. He idly loosened the collar enough she could breathe, hands playing over her idly as she rode out her orgasm. Once she started to squirm a little under the light touches, he smirked and lifted her by the thighs. A questioning sound was cut off by a moan as he started to use her like his own personal fleshlight.

**“what, did you think we were done already? silly kitten, that’s why I’m in charge.”**


	3. Visiting the Bae

**Summary for the Chapter:**

> Prompt: Somnophilia, rough sex
> 
> Pairing: Purrble / Hyperion [Outertale Sans]

Hyperion woke with a throaty moan and tears already in his sockets, teeth sunk into something soft and leathery. For a moment, utter panic filled his soul - a _much_ larger body had him pinned face-down, a long, thick, squirming, _knotted_ tentacle buried in his ass and straining his magic to the limit - before the familiar scent of smoke and leather, and burning pleasure told him it was only his… girlfriend? lover? ~~mate?~~ on a midnight visit to destroy him. More choked moans bubbled out of him as her hips slammed into him again, dick coiling inside him as she pulled halfway out, dragging each thick knot out of his already strained pucker in a way that had his eyelights rolling back into his skull and a persistent ringing filling his poor head. He let it fall forward, scrabbling uselessly at smooth sheets with his dull phalanges as another thrust ground his dick against the sopping wet pillow she’d put under his pelvis.

“go back… to sleep… Hype. I gotcha…” Definitely Purrble. How she expected him to sleep through this he wasn’t entirely sure, other than the evidence he already had slept through at least one orgasm. He couldn’t think up a snarky response, let alone get it out around the groans and yelps she kept forcing from him with every merciless movement. Even trying to lift his hips like a two gold whore wasn’t happening, every thrust drove him flat against the soft, creaky mattress again - and even if it had, it wasn’t as if she needed any help to hit every sensitive part of him. He tried to reach for her, one hand patting desperately at the arm he’d bitten in his sleep.

“aww, baby, s'okay.” She rasped against his skull, gripping his hand and slowing the punishing pace to let him attempt to coordinate his limbs. One arm managed to loop around the one in front of him, letting both his hands lace fingers with hers. The shock started to wear off then and he rattled, pressing up against her deliciously hot and solid weight. “just me~”

He tried to grumble something at her, but all that came out was a lewd bubbly noise, saliva clinging to his teeth and the tongue he hadn’t even realized he’d formed. She snickered, biting softly at his collarbone until he ground back against her. Stupid Purrble always showing up in the middle of the night, right when he was needing something to remind him that life could be good. Especially when she purred, soft form vibrating against his spine, dick curling and uncoiling in his ass with a wicked gentleness. He tried again before giving up and whining, nuzzling into her arm again. Thankfully she took pity on him, starting to move again. Even if she had to leave before Tie woke him up, he knew his body would be reminding him that there was something to hope for anyways.


	4. Sick Day

**Summary for the Chapter:**

> Someone in a chat I'm in desired "doting loving sans on a touch-starved sick person" so here ya go.

"hey sugar, you okay?" Sans plopped next to you on the couch. You huddled deeper into the throw that lived there and shook your head. Soft, curious white lights looked over you with a nearly-physical weight. His easy smile turned down, and he lifted one arm and patted his lap. "no? c'mere, lemme make it better."

You shook your head, coughing into the blanket. "Nooo, don't need to make you sick too..."

"monsters don't get human sick, you dork, now get over here." He didn't wait for you to move, scooting over a little to scoop you into his arms so you could lay comfortably against his chest. One arm wrapped securely around your waist, the other moving up to support your head and stroke your head gently. "jeeze, you're really burning up. thought you said humans don't get heat?"

You curled up to him, sacrificing one arm from the comfort of your blanket burrito to worm under his jacket. "We don't, my body's just trying to, um, cook the germs out." Your head pressed comfortably against his shoulder and you gradually relaxed with a sigh. Being sick sucked, when was the last time you got a hug, let alone cuddles?

"you're awfully snuggly for just that." He muttered, massaging your scalp slowly.

"Can't get cuddles when you're sick, that just gets the other person sick."

"now that's just cruel." The arm that had been holding you close to him shifted, working into your blanket.

"Uh-huh-- nuu, cold!" You clung tighter to him and whined in protest of the cool air disturbing your comfort.

Sans chuckled, nudging your face up towards him and nuzzling your forehead. "it's for a good cause sweetheart. you just relax an' let ol' sansy take care of everything, okay?"

"Everything?" He palmed the front of your pants and you gasped softly. "O-oh, um, okay..." You relaxed into it, fingers curling into his shirt. "Thank you." You leaned up a little to press a soft kiss to his teeth.

"that's not relaxing." He sing-songed, nipping your jaw softly and working his hand into your pants to stroke and curl his warm fingers against your sensitive flesh, slow and gentle.

"Nnnh... but Sans~" You whined, rocking into his hand.

"heh. okay, can't say no to that cute, needy face." He kissed you languidly, a broad tongue slipping past your lips to stroke along yours. His pace was perfect to keep you from choking on it.

You sighed happily, letting him rub you to a slow climax. When he was satisfied you looked more comfortable, he shifted a little to lay down, cuddling you close to his chest and tucking the blankets around both of you.

"there... just what the doctor ordered."

You snorted, nuzzling into him and drifting off.


End file.
